SO I wanted to share this. I know most people know about it but I'm sure there are a lot out there who didn't realize it yet. For those of us who aren't really good at macro (myself included), when you play 2v2,3v3 or 4v4 and you want to attack, you take your army and you move forward. But not being good at macro it means that you can't really use hotkeys to keep pumping army in your base or take care of your economy or expand..etc.. Going to attack with your army and your friends with theirs means your bases will be neglected for a few seconds, minutes.. which sometimes means Game Lost especially if your attack fails. One thing a friend of mine realized is everyone can give control to his units to one or all his allies. SOO at this point it becomes just a matter of one guy going to attack with a huge army ( controlling his allies' armies), while the others can stay back and keep pumping units or expand..or do wtv they do. I find it a very good strategy especially for people in the lower tier. My friends and I saw a significant increase in winning percentage after we realized we can do this. Just wanted to share this for beginners. It is possible to do it and it works ! Good Luck
Some friends and I did this every game for a while. We would all get first tier units, marines/marauders, zealots/stalkers, and zerglings. Everyone would pump them out as we made an early push, you really couldn't stop it unless you saw it coming. We decided to give control to the person with the best macro and or micro. We would outnumber the first base and kill the second, leaving the other two helpless.